Levels and Concentration Ratios of Polychlorinated Biphenyls and Polybrominated Diphenyl Ethers in Serum and Breast Milk in Japanese Mothers

Blood and/or breast milk have been used to assess human exposure to various environmental contaminants. Few studies have been available to compare the concentrations in one matrix with those in another. The goals of this study were to determine the current levels of polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) in Japanese women, with analysis of the effects of lifestyle and dietary habits on these levels, and to develop a quantitative structure–activity relationship (QSAR) with which to predict the ratio of serum concentration to breast milk concentration. We measured PBDEs and PCBs in 89 paired samples of serum and breast milk collected in four regions of Japan in 2005. The geometric means of the total concentrations of PBDE (13 congeners) in milk and serum were 1.56 and 2.89 ng/g lipid, respectively, whereas those of total PCBs (15 congeners) were 63.9 and 37.5 ng/g lipid, respectively. The major determinant of total PBDE concentration in serum and milk was the geographic area within Japan, whereas nursing duration was the major determinant of PCB concentration. BDE-209 was the most predominant PBDE congener in serum but not in milk. The excretion of BDE 209 in milk was lower than that of BDE 47 and BDE 153. QSAR analysis revealed that two parameters, calculated octanol/water partition and number of hydrogen-bond acceptors, were significant descriptors. During the first weeks of lactation, the predicted partitioning of PBDE and PCB congeners from serum to milk agreed with the observed values. However, the prediction became weaker after 10 weeks of nursing

Influence of dioxin exposure upon levels of prostate-specific antigen and steroid hormones in Vietnamese men

Most studies on the relationship between Agent Orange and prostate cancer have focused on US veterans of the Vietnam War. There have been few studies focusing on the relationship between levels of prostate-specific antigen (PSA) and dioxins or steroid hormones in Vietnamese men. In 2009–2011, we collected blood samples from 97 men who had resided in a “dioxin hotspot” and 85 men from a non-sprayed region in Vietnam. Then levels of PSA, dioxins, and steroid hormones were analyzed. Levels of most dioxins, furans, and non-ortho polychlorinated biphenyls were higher in the hotspot than those in the non-sprayed region. Levels of testosterone, dehydroepiandrosterone, and estradiol differed significantly between the hotspot and the non-sprayed region, but there were no correlations between levels of PSA and steroid hormones and dioxins in either of the two regions. Our findings suggest that PSA levels in Vietnamese men are not associated with levels of dioxin or steroid hormones in these two regions. © 2016 Springer-Verlag Berlin HeidelbergEmbargo Period 12 month

The Relationship of Dioxin Levels in Serum of 9-Year-Old Vietnamese Children and Their Mothers’ Breast Milk

In this study, we measured the concentrations of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) in the blood of 9-year-old children living in a dioxin hotspot area and a nonexposed area in Vietnam. Forty-five blood samples were collected in the hotspot area while twelve pooled blood samples were collected in the nonexposed area. We found that the dioxin level of children in the hotspot was significantly higher than that of children in the nonexposed area. The total TEQ of PCDD/Fs in the hotspot and the nonexposed was 10.7 and 3.3 pg TEQ/g fat, respectively. However, TCDD, the maker of Agent Orange, was not detected in the blood of children in the hotspot area. In the hotspot area, four congeners 1,2,3,4,6,7,8-HpCDD, 1,2,3,4,7,8-HxCDF, 1,2,3,6,7,8-HxCDF, and 1,2,3,4,6,7,8-HpCDF in mothers’ breast milk showed a significantly positive correlation with those in children’s serum although the correlations of 1,2,3,7,8-PeCDD and 2,3,4,7,8-PeCDF were not significant. In addition, the duration of breastfeeding also correlates with dioxins in children. These results suggested that children in the hotspot area were exposed to dioxin through mothers’ milk and other foods or environmental factors. The present study is the first study that shows dioxin levels in Vietnamese children

Biological Monitoring of human exposure to neonicotinoids using urine samples, and neonicotinoid excretion kinetics

[Background] Neonicotinoids, which are novel pesticides, have entered into usage around the world because they are selectively toxic to arthropods and relatively non-Toxic to vertebrates. It has been suggested that several neonicotinoids cause neurodevelopmental toxicity in mammals. The aim was to establish the relationship between oral intake and urinary excretion of neonicotinoids by humans to facilitate biological monitoring, and to estimate dietary neonicotinoid intakes by Japanese adults. [Methodology/Principal Findings] Deuterium-labeled neonicotinoid (acetamiprid, clothianidin, dinotefuran, and imidacloprid) microdoses were orally ingested by nine healthy adults, and 24 h pooled urine samples were collected for 4 consecutive days after dosing. The excretion kinetics were modeled using one- and two-compartment models, then validated in a non-deuterium-labeled neonicotinoid microdose study involving 12 healthy adults. Increased urinary concentrations of labeled neonicotinoids were observed after dosing. Clothianidin was recovered unchanged within 3 days, and most dinotefuran was recovered unchanged within 1 day. Around 10% of the imidacloprid dose was excreted unchanged. Most of the acetamiprid was metabolized to desmethyl-Acetamiprid. Spot urine samples from 373 Japanese adults were analyzed for neonicotinoids, and daily intakes were estimated. The estimated average daily intake of these neonicotinoids was 0.53-3.66 μg/day. The highest intake of any of the neonicotinoids in the study population was 64.5 μg/day for dinotefuran, and this was <1% of the acceptable daily intake

1年間のFBRA摂取による油症原因ダイオキシン類の体外排泄促進

特集号 油症とPCB及びダイオキシン関連化合物 研究報告第20集 責任編集者 古江増隆The Twentieth Reports of the Study on Yusho―PCBs and Dioxin-Related Compounds―Guest Editor Masutaka FurueThirty-six years have passed since the outbreak of Kanemi rice oil poisoning, namely, Yusho in the western Japan. However, even now the patients with Yusho have been still suffering from several objective and subjective symptoms. In order to improve or, if possible, to cure the such symptoms, the most important therapeutic treatment is considered to actively excrete the causative agents, that is, polychlorinated dibenzofurans (PCDFs) and polychlorinated dibenzo-p-dioxins (PCDDs) from the bodies of the patients and to reduce their body burdens. In rats, dietary fiber and chlorophyll have been shown to promote the fecal excretion of dioxins and to reduce their levels in rat liver. In this study, we examined whether such kinds of effect were also observed by FBRA, which was the health food and relatively rich with dietary fiber and chlorophyll, in nine married Japanese couples. As a result, concentrations of PCDFs and PCDDs on the lipid weight basis in the blood of the FBRA-intake group in which they took 7.0 to 10.5g of FBRA after each meal and three times a day for one year were more lowered than those in the blood of the nonintake group ; Blood levels of PCDFs and PCDDs in the FBRA-intake group were decreased by 41.0 and 37.2 %, respectively, and those decreases were 33.7 and 29.4 % in the non-intake group. Their total bod y burdens just before and one year after the study were calculated on the assumptions that the body fat was also contaminated with these dioxins at their blood levels on the lipid weight basis and the content of body fat was 20 % of the body weight. Then, we computed the average amounts in excretion of PCDFs and PCDDs from the body in both the FBRA-intake and non-intake groups. Consequently, the amounts of excretion of PCDFs and PCDDs in the FBRA-intake group were 1.81 and 1.74 times, respectively, greater than those in the non-intake group. Therefore, FBRA seemed to promote the fecal excretion of causative agents of Yusho, from the human body. We also expect FBRA to reduce their body burdens of patie nts with Yusho and to improve some objective and subjective symptoms of Yusho patients.カネミ油症中毒事件が発生してから36年が経過したが,今でも油症患者は種々様々な自覚および臨床症状で苦しんでいる.このような症状を改善し治療するには,その主要な原因物質であるポリ塩化ダイベンゾフラン(PCDFs)とポリ塩化ダイベンゾーp一ダイオキシン(PCDDs)を積極的に体外へ排泄し,汚染レベルを低下させることが第一である.この研究では動物実験によりダイオキシン類の体外排泄促進作用が認められている食物繊維と葉緑素を比較的多量に含む栄養補助食品FBRA(発酵玄米栄養補助食品ハイ・ゲンキ,㈱玄米酵素,本社:北海道札幌市)によるカネミ油症原因物質の体外排泄促進を9組の夫婦の協力により調べた.その結果,毎食後7～10.5gのFBRAを1日3回1年間摂取することにより,血液脂質重量当りのPCDFsとPCDDsの濃度が非摂取群よりもそれぞれ6.2%と7.7%低下した.この血液脂質濃度で体脂肪も汚染されており,体脂肪率を体重の20%と仮定し,1人当り1年間の体外排泄量を両化学物質について計算した.そうすると,FBRAを摂取することによりPCDFsとPCDDsの排泄量がそれぞれ1.81倍と1.74倍高まることが示された.以上のような結果より,FBRAは油症原因物質のPCDFsとPCDDsの体外への排泄を促進するので,油症患者の治療にも有効と考えられた